Iiellmitth kranich and jacques bach



(No Model.)

H. KRANIOH & J. EACH.

PIANO ACTION.

Ne. 411,248. Patented Sept. 17, 1889.

UNITED STATES PATENT OFFICE.

HELLMUTH KRANICH AND JACQUES EACH, OF NE\V YORK, N. Y.

PIANO-ACTION.

SPECIFICATION forming part of Letters Patent No. 411,248, dated September 17, 1889.

Application filed October 16, 1888. Serial No. 288,267. (No model.)

To all whom it may concern.-

Be it known that we, HELLMUTH KRANICH and J AOQUES EACH, of New York, in the county and State of New York, have invented a certain new and useful Improvement in Piano-Forte Actions, of which the following is a specification.

\Ve will describe parts of a piano-forte action embodying our improvement, and then point out the novel features in the claims.

In the accompanying drawings, Figure 1 is a partly-sectional side view of certain parts of a piano-forte action. In this view certain parts are represented in section. Fig. 2 is a top View of the repeating-lever and the jack. Fig. 3 is a front view of the jack and the j acksupporting lever.

Similar letters of reference designate corresponding parts in all the figures.

A designates one of the keys of the pianoforte action. It may be of the ordinary or any suitable construction. It is shown as fulcrumed between the ends upon a rail a. At the rear end it carries a check a for the hammer.

B designates the hammer. Its helve or shank is pivotally connected to a block 1), secured to a rail B. The hammer helve or shank is provided with a projection or nose Z2 upon which a jack 0 operates.

D designates the hammer-rest rail which may be supported in any desirable manner. As here shown, it is represented as being supported from a rail E, which supports the lower lever F. The lower lever F is at one end pivotally connected to a block F, secured to the rail E. It extends forwardly over the key, and is oscillated up and down by the latter in a well-known manner. The key is shown as provided with an adjustable screw aiwhich operates against a downward projection of the lower lever F. The jack 0 consists of an elbow-lever fulcrumed in the forward end of the lower lever F, the latter being bifurcated to receive it. The repeating-lever R is pivoted between the ends in a bifurcate extension of the lower lever F. The repeating-lever is forked or slotted at the forward end and the upper arm of the jack extends into the fork or slot. The forward end of the repeating-lever operates in conjunction with an adjustable stop G, consisting of an adjustable screw in the block, to which the hammer helve or shank is connected. The rear end of the repeatinglever has extended downwardly through it a screw H, carrying afoot-piece 72 adapted to bear upon the lower lever F. A hook-shaped wire I extends upwardly from the lower lever and over the rear portion of the repeatin g-lever, limiting its motion. The forwardly-extcnding arm of the jack operates in conjunction with an adjustable stop J, arranged in an extension of the rail, to which the hammer-blocks are secured.

K designates a spring consisting of a wire coiled at about the middle of its length around a pin extending through the upward bifurcate extension of the lower lever F. The lower limb of the wire engages with the upwardly-extending arm of the jack. The upper limb of the wire operates in conjunction with the forward portion of the repeating lever. As here shown, the upper limb of the spring K is bent approximately into circular form and bears against the concave lower face of the block or disk L, fitted into a cavity in the under side of the forward portion of the repeating-lever. A screw M extends through this portion of the lever and bears against the top of the block. By adjusting this screw the force of the spring will be regulated and the power of the hammer in repeating may be easily varied. This means of adjustment is very simple and accessible.

The jack 0 has a projection or third arm 0' extending from it downwardly below the bifurcate portion of the lower lever, in which the jack is fulcrumed. The lower lever is also provided adjacent to its bifurcate forward end with a projection f, extending downwardly from the lower side. A screw N, having a head (here shown as a block of wood) fitted to it and faced on the rear side with felt or other suitable material, passes loosely through the projection or third arm 0 of the jack and engages with the projection f of the lower lever F. The head of the screw bears against the forward side of the projection or third arm of the jack, the soft facing of the head being in contact therewith. This screw forms a simple and effective adjustment for the jack. By manipulating the screw the required amount of force can be brought to bear upon the nose of the hammer-shank and Varied or adjusted at will. The strikingforce of the hammer upon the string can thus be governed.

This improvement obviates the necessity for the cloth or soft felt, which is ordinarily glued in the fork of. the repeating-lever in which the upper arm of the jack works and upon which the jack when not in operation rests. As the head of the screw holds the jack in one direction and the spring maintains it against movement'in the other direction while at rest, the cloth or felt in the fork of the repeating-lever is no longer necessary.

It is of importance to dispense with the cloth or felt in the fork of the repeating lever. Its presence is objectionable, because the varying eifects incident to changes in atmospheric conditions do not act upon it to cause it to contract and expand correspondingly to the other parts. Owing to changes in the other parts incident to' variations in atmospheric conditions, and the failure of the cloth or felt to respond to such changes, the jack is, when the cloth or felt is employed, alternately too strong or too weak, and so interferes with the touch and operation of the action. The presence of the felt or cloth is also objectionable, because the friction of the jack in motion will in time raise the surface of the felt, so that the jack will lose its grip upon the hammer to operate it to the string, and the movement of the hammer will sometimes through this cause fail to produce any result.

So convenient and accessible is the screw for adjusting the jack that it may be manipulated without removing the action and the necessary appendages. It will be only neces sary with this means of adjust-lnentto remove the fall-board, whereupon the screw will be perfectly accessible. The leverage of the jack, at the third arm or projection or eye, as it may be termed, is so little that the slightest turn of the screw passing through the same will suflice for adjusting the jack properly under the nose of the hammer-shank and give it the strength desired.

What weclaim as ourinvention, and desire to secure by-Letters Patent, is-

1. The combination, with a jack and asupport for the jack, of a projection, arm, or eye extending from the jack,aprojection extending from the support of the jack, and a screw having ahead acting against the projection, arm, or eye of the jack and engaging with the projection on the jack-support, substantially as specified. i

2. The combination, with a jack and a support for the jack, of a projection, arm, or eye extending from the jack, a projection extending from the support of the jack, and a screw extending below the forward arm of the jack passing through the projection, arm, or eye of the jack and engaging with the projection on the jack-support, substantially as specified.

3. The combination, with a jack, asupport for the jack, and a repeating-lever, of a spring having connection with the jack and its support, and an adjustable block on the repeating-lever bearing on one end of said spring, substantially as specified.

HELLMUTH KRANIOH. JACQUES BAOH. Witnesses:

WILLIAM ScHUTz, FRED KRANICH. 

